package com.tom;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


/**
 * Servlet Filter implementation class imageFilter
 */
public class imageFilter implements Filter {

    /**
     * Default constructor. 
     */
    public imageFilter() {
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see Filter#destroy()
	 */
	public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
		HttpServletRequest request = (HttpServletRequest) req;
		HttpServletResponse response = (HttpServletResponse)res;
		String referer = request.getHeader("referer");
		
		if(referer == null || ! referer.contains(request.getServerName())){
			request.getRequestDispatcher("/error.gif").forward(request, response);
		}else{
			chain.doFilter(request, response);
		}
		
		
		chain.doFilter(request, response);
	}

	/**
	 * @see Filter#init(FilterConfig)
	 */
	public void init(FilterConfig fConfig) throws ServletException {
		// TODO Auto-generated method stub
	}

	public void destroy() {
		// TODO Auto-generated method stub
	}
	
	/**
	 * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
	 */
}
